Umbrellas provide users protection against the environment and can range from small handheld umbrellas to large industrial sized umbrellas which may exceed 11 feet in radius. The instant invention generally relates to (but is not limited to) large industrial type umbrellas which are 5 feet in diameter or more such as patio umbrellas.
These industrial umbrellas are often used in environments where there is high wind or wind gusts and therefore the umbrellas must be both strong and durable. Often these umbrellas are left onsite indefinitely and continually endure a variety of weather conditions which creates wear on the umbrellas. Maintenance and support of these industrial umbrellas requires replacement of worn and broken elements as needed. The durability of the umbrella as well as the ease of maintenance and support are key aspects of the usefulness of the umbrella. Other important aspects of the umbrella include the umbrella aesthetics as well as accessories attachable or integrated into the umbrella.
The ease of operation of the umbrella is another critical factor in selection of an umbrella and key components which effect the operation of the umbrella include the umbrella hub assembly, the umbrella ribs, the joints interconnecting the ribs and the hub, the fabric covering the umbrella ribs, and (optionally) a pulley system to aid in opening and closing the umbrella assembly.
Additionally an umbrella system may further include a unique base or stand for supporting the umbrella assembly and the umbrella system may include accessories such as lighting components.
Overall, an umbrella assembly is only as strong as its weakest link! Largely, umbrella system retailers, commercial/industrial users, and umbrella system equipment manufacturers select and rate umbrellas on their durability and maintainability. The key components listed above are often essential factors in the determination of an umbrella's suitability for use in a particular environment and for a particular customer.
A variety of patents and patent publications disclose umbrella assemblies which provide unique hubs and key elements for pivotally connecting umbrella assembly ribs to other umbrella assembly components or for interconnecting umbrella assembly components. These include (U.S. Pat. No. 7,556,051, U.S. Pat. No. 7,533,680, U.S. Pat. No. 7,111,954), and Patent Application Publications (US 20080202570, US 20070062565, US 20070056615). Particularly, patents exist which teach methods for securing mounting brackets to an umbrella hub. For example, U.S. Pat. No. 7,318,444 provides a hub assembly having upper and lower portion ledges which abut a hub channel in which a bracket band is seated where upper and lower ledges provide a mounting bracket holding force created by squeezing against the periphery of the bracket band. Also, various patents provide limited solutions for securing for securing mounting brackets to an umbrella hub such as the use of a screw inserted into the center of strut bracket members (U.S. Pat. No. 7,293,573, U.S. Pat. No. 6,889,699, U.S. Pat. No. 6,386,214, U.S. Pat. No. 6,314,976).
These patents often sacrifice ease of bracket installation and replacement over hub/bracket assembly combination strength and rigidity.
A need exists for a hub assembly and mounting bracket combination which is both easy to install or remove and which is extremely rigid and capable of withstanding high wind gusts and other high external forces.